Honeybees pollinate many of our favourite fruits and vegetables, but in large parts of some developed countries there are not enough bees to do this job naturally or efficiently.

So farmers employ a practice called migratory beekeeping: they truck hives into their fields, where the bees live for short periods to pollinate the crops during the plants’ most fertile window.

An in-depth Scientific American article outlines just how important this practice is to farming and what effect it has on our ecosystem.

The magazine estimated that without migratory beekeeping, the United States would lose one-third of its crops.

And it does involve cruelty to bees, according to Scientific American: “Forcing bees to gather pollen and nectar from vast swathes of a single crop deprives them of the far more diverse and nourishing diet provided by wild habitats. The migration also continually boomerangs honeybees between times of plenty and borderline starvation.

“Once a particular bloom is over, the bees have nothing to eat, because there is only that one pollen-depleted crop as far as the eye can see. When on the road, bees cannot forage or defecate. And the sugar syrup and pollen patties beekeepers offer as compensation are not nearly as nutritious as pollen and nectar from wild plants.”

Average shoppers can’t avoid produce that involved migratory beekeeping any more than they can avoid driving on asphalt

Tracy Reiman, Peta executive vice-president

Not to mention, the commingling of bees from across the country in the same farms spreads disease, which can lead to colony collapse disorder.

But here’s what the debate hasn’t mentioned: avocados and almonds aren’t the only crops that are pollinated in this manner.

Migratory beekeeping is a slippery slope that – for those who wish to avoid it – could change the scope of veganism.

Other fruits and vegetables that may be produced through migratory pollination include apples, plums, cherries, alfalfa, blueberries, watermelon, cantaloupe, cucumbers, pumpkin, lettuces, squash and tangerines.

Not every item in these categories is produced in this manner, but unless a vegan were to know the practices of the farm of origin, they would have no way of knowing whether bees were exploited in the making of that squash salad.

People for the Ethical Treatment of Animals (Peta) has a strong stance against honey.

“These tiny animals are factory-farmed, much like chickens, pigs, and cows are,” says the organisation’s page on honeybees. “Avoid honey, beeswax, propolis, royal jelly, and other products that come from bees.”

The Peta website also includes a round-up of “the best vegan recipes for avocado lovers”, including chocolate avocado pudding and tofu-stuffed avocados.

In a statement about its stance on migratory beekeeping, Peta executive vice-president Tracy Reiman said: “Going vegan is about making kind choices that bring about positive change. Average shoppers can’t avoid produce that involved migratory beekeeping any more than they can avoid driving on asphalt, which has animal ingredients – but they can save nearly 200 animals’ lives every year by choosing plant-based foods instead of meat, eggs, and dairy ‘products’.”

Asked to clarify how migratory beekeeping is different from honey, given that bees are mistreated in both cases, Peta senior media liaison Catie Cryar wrote in an email that, while it’s difficult to avoid fruit and vegetables that have been created through migratory beekeeping, “everyone can easily avoid honey, which is made by bees for bees, and instead enjoy delicious vegan options such as agave nectar”.

Veganism “shouldn’t be about adhering to rigid dogma for dogma’s sake but rather about making choices that bring about positive change. Ideally, the use of products that involve harming animals should be avoided, but it’s impossible to be 100 per cent ‘pure,’ ” she said.

Veganism may be the most philosophical of all diets, thanks to the constant moral relativist quandaries it entails. Some studies have questioned whether insects, particularly bees, are capable of feeling pain.

And others – even such vegan groups as Direct Action Everywhere – point out that a vegan diet is hardly “cruelty free”, in that it involves the exploitation of migrant farm workers or the potential poisoning via pesticides of wild animals that live near farms.

Veganism cannot eliminate suffering, but its adherents can feel like they have not personally contributed to it.

So will vegans give up their avocado salads? Maybe the most hardcore ones will. But those who want to continue to slurp avocado smoothies have Peta’s blessing – as long as they don’t put honey in them.